The lunar rover portion of China’s Chang’e-4 lunar probe recently had a milestone after traveling 565.9 meters, as of Saturday, since leaving the lander portion behind. According to the China National Space Administration, the lander and the rover have been switched to dormant mode for the lunar night after operating stably for the 23rd lunar day.
The lander was switched to dormant mode at 9:40 PM Friday Beijing time as scheduled, and the rover, known as Yutu-2, was switched into dormant mode at 12 PM Friday. Days are much longer on the Moon; they are equal to 14 days on Earth. A lunar night spans 14 days here on Earth.
The rover and lander are switched to dormant mode during the night due to the lack of solar power. So far, both have survived 660 Earth days on the far side of the moon. Yutu-2 spent its 23rd lunar day traveling northwest toward an area featuring basalt and an impact crater with high reflectivity. During its trip to the crater, the near-infrared spectrometer aboard the rover detected a rock about 30 centimeters in diameter.
Data transmitted back to Earth about the rock is being analyzed. One of the most critical features of the mission is that scientists are carrying out the first measurements of radiation on the moon. Radiation data is being acquired using a neutron radiation detector aboard the rover. The surface of the moon is highly radioactive.
A study showed that the Moon’s surface is approximately 2 to 3 times as radioactive as the International Space Station. It’s 300 times more radioactive than the surface of the Earth in Beijing. Dealing with space radiation is one of the biggest challenges humans face as they look for a sustained presence on the Moon and Mars in the future.